Index: wp-admin/link-manager.php
===================================================================
--- wp-admin/link-manager.php	(revision 6574)
+++ wp-admin/link-manager.php	(working copy)
@@ -129,7 +129,10 @@
 			$short_url = substr($short_url, 0, 32).'...';
 
 		$visible = ($link->link_visible == 'Y') ? __('Yes') : __('No');
-		++ $i;
+		if ( isset($i) ) 
+			++ $i;
+		else
+			$i = 1;
 		$style = ($i % 2) ? '' : ' class="alternate"';
 		?><tr id="link-<?php echo $link->link_id; ?>" valign="middle" <?php echo $style; ?>><?php
 		foreach($link_columns as $column_name=>$column_display_name) {
Index: wp-admin/plugin-editor.php
===================================================================
--- wp-admin/plugin-editor.php	(revision 6574)
+++ wp-admin/plugin-editor.php	(working copy)
@@ -55,7 +55,7 @@
 	if ( !current_user_can('edit_plugins') )
 		wp_die('<p>'.__('You do not have sufficient permissions to edit plugins for this blog.').'</p>');
 
-	if ( $_GET['liveupdate'] ) {
+	if ( ! empty($_GET['liveupdate']) ) {
 		check_admin_referer('edit-plugin-test_' . $file);
 		$current = get_option('active_plugins');
 		$plugin = $file;
Index: wp-admin/edit-pages.php
===================================================================
--- wp-admin/edit-pages.php	(revision 6574)
+++ wp-admin/edit-pages.php	(working copy)
@@ -41,7 +41,7 @@
 
 <form name="searchform" id="searchform" action="" method="get">
 	<fieldset><legend><?php _e('Search Terms&hellip;') ?></legend>
-		<input type="text" name="s" id="s" value="<?php echo attribute_escape( stripslashes( $_GET['s'] ) ); ?>" size="17" />
+		<input type="text" name="s" id="s" value="<?php echo ( isset($_GET['s']) ) ? attribute_escape( stripslashes( $_GET['s'] ) ) : ''; ?>" size="17" />
 	</fieldset>